Engine fuel and transmission control



Dec. 30, 1969 R. D. WREN, JR 3,486,594

' ENGINE FUELAND TRANSMISSION CONTROL 2 Sheets-Sheet 1 Filed Feb. 29, 1968 Fig./

Robert D.-Wren, Jr.

' INVENTOR.

WWW MQ,

'Dec.30.1969 R. 15. mm, JR 3,486,594

ENGINE FUEL AND TRANSMISSION CONTROL Filed Feb. 29, 1968 2 Sheets-Sheet 2 Fig.3 3

IN VENTOR.

I Roberf D. Wren, Jr.

MEM

US. Cl. 192-062 6 Claims ABSTRACT OF THE DISCLOSURE Apparatus for reducing or cutting off flow of fuel from a carburetor to the intake manifold of an internal combustion engine during deceleration or low fuel demand. Auxiliary air is supplied directly to the intake manifold from the air cleaner bypassing the carburetor during deceleration conditions. A normally opened needle valve in the idle circuit of the carburetor is temporarily closed when a driver moves his foot fromthe accelerator pedal to cause deceleration of the motor vehicle. Cut-off of fuel by the needle valve and opening of the air bypass is simultaneously effected through solenoid operated valves upon release of the accelerator pedal only if a decelerating condition of the vehicle propulsion system is sensed as distinguished from an idle condition when the vehicle is substantially stationary.

The present invention relates to the internal combustion engine art and more particularly pertains to a novel apparatus for minimizing the passage of unburned fuel through the engine under low fuel demand conditions.

When an internal combustion engine in a motor vehicle is coupled to the driving wheels through a power transmission, for propelling the vehicle under positive acceleration conditions, the conventional carburetor functions reasonably efficiently as a supplier of fuel and air to the intake manifold and the engine operates reasonably efiiciently. However, when the vehicle is decelerated, the conventional carburetor becomes extremely inefiicient because the vacuum applied to the interior of the carburetor increases to such an extent as to increase the flow of gasoline through the idling valve assembly of the carburetor. It is under such deceleration conditions, that the engine requires a minimum amount of fuel to meet minimal power output requirements. Under such deceleration conditions, an excessive quantity of fuel is supplied to the engine and much of it passes unburned through the engine. Accordingly, unburned fuel emitted from the exhaust system of the engine increases the quantity of hydrocarbon pollutants in the engine exhaust which according to authorities on the subject is one of the major contributing causes of atmospheric pollution. Furthermore, ,the unburned fuel which passes through the engine constitutes a waste of fuel to increase the operating costs of the motor vehicle. Also, passage of excessive fuel such as gasoline through the cylinders of the engine results in the dilution of the engine lubricating oil by the raw gasoline. The resultant removal of lubricant from the surfaces which should be coated by the lubricating oil, leads to increased wear on the internal moving parts of the engine and severe scoring of the cylinder walls. The raw gasoline passing through the engine also tends to dilute all of the oil stored within the crankcase of the engine and thinning it to such a degree that it loses its protective lubricating qualities. All parts of the engine normally lubricated by the crankcase oil will accordingly suffer.

It is therefore an important object of the present invention to minimize the foregoing wasteful and harmful United States Patent "ice effects caused during deceleration of a vehicle propulsion system by cutting off or blocking the flow of fuel into the intake manifold of the engine as well as to supply fuel diluting air in bypass relation to the carburetor under proper deceleration conditions when such corrective action is desirable.

In accordance with the present invention, the system of the present invention is applicable to conventional vehicle propulsion systems having an internal combustion engine and a fuel supply device such as a carburetor through which a mixture of air and gasoline is fed to the intake manifold under a suction pressure developed within the manifold. A solenoid operated flow blocking valve is accordingly connected to the idle valve circuit of the carburetor in order to interrupt flow of fuel to the intake manifold simultaneously with the opening of a bypass passage through which air is supplied to the manifold under the suction pressure developed therein. A solenoid operator is accordingly connected to the bypass control valve for opening the same at the same time that the solenoid operated fuel cut-off valve is closed. Both solenoid operators are connected to a source of electrical energy such as the vehicle battery upon release of the accelerator pedal which controls a disabling switch. Further, operation of the system occurs only under decelerating conditions as sensed by a pressure responsive switch connected to the fluid transmitter associated with the engine transmission in one form of the invention. Since a substantial internal pressure is developed in the fluid transmitter only when substantial power is being transmitted therethrough, the pressure responsive switch will detect an idling condition wherein the vehicle is either stationary or moving because of creep and prevent operation of the solenoid valves. Where the vehicle propulsion system employs a standard slidable gear transmission, the deceleration condition of the vehicle propulsion system is sensed by switch devices respectively controlled by the clutch pedal and the gear shift selector. Thus, disengagement of the clutch by the clutch pedal or placement of the gear shift lever in its neutral position prevents operation of the fuel cut-off system since the vehicle propulsion system would then be in an idling condition.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a simplified side elevational view of a vehicle propulsion system with which the apparatus of the present invention is associated.

FIGURE 2 is a schematic diagram illustrating the fuel cut-off system of the present invention.

FIGURE 3 is an enlarged side elevation view with parts shown in section of the solenoid operated bypass air valve associated with the apparatus of the present invention.

FIGURE 4 is an enlarged side elevational view with parts shown in section of the solenoid operated fuel cutoff valve mechanism associated with the present invention.

FIGURE 5 is an enlarged partial sectional view through the pressure responsive switch mechanism associated with the apparatus illustrated in FIGURE 1.

FIGURE 6 is a side elevational view with parts shown in section of some of the controls associated with a fuel cut-off apparatus for another type of vehicle propulsion installation.

FIGURE 7 is a side elevational view with parts shown in section of other controls associated with the system to which FIGURE 6 pertains.

FIGURE 8 is a schematic illustration of the system associated with FIGURES 6 and 7.

FIGURE 9 is a partial top plan view showing the installation of the solenoid operated bypass air valve illustrated in FIGURE 3.

Referring now to the drawings in detail, FIGURE 1 illustrates a typical vehicle propulsion system for a conventional automotive vehicle. The propulsion system generally referred to by reference numeral 10 includes an internal combustion engine 12 having an intake manifold 14 to which a conventional type of carburetor 16 is connected for supply of an air-fuel mixture. An air cleaner 18 is connected to the top of the carburetor for filtering the intake air in the usual manner. A throttle lever 20 is also associated with the carburetor 16 for regulating the inflow of fuel mixture to the intake manifold when pivotally displaced between an open and closed throttle position. The throttle lever 20 is accordingly connected by the throttle linkage 22 to an accelerator pedal 24 constituting the fuel control element of the engine. The output of the engine is thereby regulated to drive the wheels of the vehicle through an automatic type of transmission 26 having a fluid transmitter such as a hydraulic torque converter constituting the power coupling between the engine and the gearing of the transmission. As is well known in the art, fluid transmitters include bladed rotor elements that increase the internal static pressure of the fluid medium through which torque is transmitted, as the rotor elements increase in rotational speed. This pressure of the fluid medium may be used as a switch actuating signal as hereinafter explained.

In accordance with the present invention, a solenoid operated fuel cut-off valve mechanism 28 is connected to the carburetor so that when energized it will interrupt or block the flow of fuel mixture through the idle circuit of the carburetor thereby completely cutting off the supply of fuel to the engine upon release of the accelerator pedal 24. A solenoid operated valve mechanism 30 on the other hand is mounted on the intake manifold for controlling the flow of air to the intake manifold in bypass relation to the carburetor through a bypass conduit 32 interconnected between the air cleaner 18 and the intake manifold. Thus, the solenoid operated valve mechanisms 28 and 30 and the bypass conduit 32 form part of the fuel cut-off apparatus of the present invention which also includes a disabling switch mechanism 34 controlled by the accelerator pedal 24 and a pressure-responsive switch device 36 connected to the fluid transmitter of the transmission 26.

As diagrammatically shown in FIGURE 2, the fluid transmitter referred to by reference numeral 38 is opera tive to close the switch device 36 when a substantial internal pressure is sensed exceeding the internal pressure existing within the fluid transmitter under idle or creeping conditions. The switch device 36 is connected in series with the disabling switch device 34 which is normally closed and adapted to be opened upon actuation of the accelerator pedal 24. The switch devices 34 and 36 are connected in series between a source of electrical energy such as the vehicle battery 40 and the parallel connected, solenoid operated valve mechanisms 28 and 30. It will be apparent therefore, that only when the accelerator pedal 24 is released and a suflicient internal pressure exists within the fluid transmitter 38 representative of engine power output in excess of that under idling conditions, will an energizing circuit be completed to operate the valve mechanisms 28 and 30. Release of the accelerator pedal and the existence of a substantial internal pressure within the fluid transmitter is of course indicative of a low fuel demand, decelerating condition of the vehicle propulsion system resulting in cut-off of fuel by means of the valve mechanism 28 and supply of bypass air to the intake manifold through the valve mechanism 30.

Referring now to FIGURES 3 and 9, it will be observed that the solenoid operated valve mechanism 30 includes a valve chamber portion 42 connected between the air bypass conduit 32 and the intake manifold 14. A butterfly valve member 44 is pivotally mounted within the valve chamber and normally engages an internal valve seat formation 46 as shown by solid line in FIGURE 3 blocking flow of air through the bypass conduit 32 into the intake manifold. The valve member 44 is connected to a pinion gear 48 so that it may be pivotally displaced from its closed position to an open position shown by dotted line in FIGURE 3 upon pivotal displacement of a sector gear 50 with which the pinion 48 is in mesh. The sector gear is pivotally connected by the link 52 to one end of an armature shaft 54 projecting from an armature core 56. The armature core 56 is slidably mounted within a tubular coil form 58 on which a solenoid winding 60 is mounted. The solenoid winding is enclosed within an outer solenoid housing 62 clamped to the valve conduit by the mounting clamp 64. The armature shaft 54 slidably extends through the end Wall 66 of the solenoid housing, the other end of the armature shaft terminating in a head portion 68. Mounted on the shaft is a biasing spring 70 reacting between the head portion 68 and an insulating spacer 72 abutting the solenoid Winding 60 within the housing in axially spaced relation to a non-conductive end wall 74 through which the head portion 68 of the armature shaft is exposed. A pair of conductive pins 76 extend through the insulating spacer 72 and end wall 74 so as to electrically connect the ends of the solenoid winding 60 to the terminals 80 mounted on the end wall 74 in insulated relation to the solenoid housing. The terminals 80 con- "nect the solenoid winding to the energizing circuit as aforementioned in parallel with the terminals 82 associated with the solenoid operated valve mechanism 28 as more clearly shown in FIGURE 4.

The valve mechanism 28 includes a solenoid device similar to that described in connection with the valve mechanism 30. This solenoid device accordingly includes a housing 84 enclosing a solenoid winding 86 mounted on a tubular coil form 88 within which an armature core 90 is slidably mounted. The armature core is displaceable between an end wall 92 of the solenoid winding and an insulating spacer 94 through which the conductive pins 96 extend to electrically connect the winding leads to the terminals 82 mounted on the non-conductive end wall 98. The armature shaft extending through the armature core 90 mounts on one side thereof, a biasing spring 100 reacting between the head portion 102 and the spacer 94 to normally bias the armature core to one position as illustrated in FIGURE 4. The solenoid winding is fixedly mounted on the carburetor by means of a suitable mounting clamp 104 and is threadedly connected by means of the tubular extension 106 to the idle circuit portion of the carburetor. The armature shaft 108 extends through the tubular extension 106 and is provided with a conical valve formation 108 at its outer end adapted to close the idle circuit passage of the carburetor when seated on the conical valve seat 110. It will be apparent, that the spring 100 normally holds the valve formation 108 in its open position as illustrated in FIGURE 4. Upon energization of the solenoid winding 86 however, the armature shaft is axially displaced against the bias of the spring 100 to close the valve blocking flow of fuel through the idle circuit passage of the carburetor. Since the accelerator pedal will at that time be released, no flow of fuel into the intake manifold will occur. At the same time, the solenoid winding 60 associated with the valve mechanism 30 is energized causing displacement of the armature shaft 54 against the bias of spring 70 and movement of the valve 44 to an open position permitting the flow of bypass air into the intake manifold.

The pressure-responsive switch device 36 as shown in FIGURE 5, includes a tubular housing 112 having an internally threaded inlet 114 adapted to be connected through a conduit to the fluid transmitter 38. Internal pressure of the fluid transmitter is accordingly communicated with the bellows 116 enclosed within the tubular housing 112 to which a switch actuator shaft 118 is connected. A spring 120 within the tubular housing 112 reacts between the bellows and the externally threaded adjusting nut 122 through which the actuator rod slidably extends. Thus, when a suficiently high pressure is internally developed within the fluid transmitter, it will axially displace the bellows and the actuator shaft 118 against the bias of thespring 120 to cause closing of the switch device 36 in order to operatively condition the energizing circuit for the solenoid operated valve mechanisms 28 and 30 as aforementioned. I

The fuel cut-01f system has been hereinbefore described in connection with an automatic transmission installation utilizing the pressure-responsive switch device 36 to condition the fuel cut-off system for operation when a torque transmitting condition of the transmission is sensed. Where a standar slidable gear-type transmission is involved, the fuel cut-01f apparatus of the present invention is modified by replacement of the pressure responsive switch device with a pair of switch devices 124 and 126 as shown in FIGURES 6, 7 and 8. The switch device 124 may be mounted in any suitable location for opening upon actuation of the clutch pedal 128 causing disengagement of the usual clutch mechanism through which the engine is coupled to the transmission. The switch device 126 on the other hand is mounted for engagement by a switch actuator 130 connected to a gear shift ratio selector 132. The switch device 126 is held open when engaged by the actuator 130 corresponding to a neutral position of the gear shift lever 132. Accordingly, the switch device 126 is closed only when the transmission is in a torque transmitting condition.

As shown in FIGURE 8, the switch devices 124 and 126 are connected in series to the battery source of voltage 40' in order to complete an energizing circuit for the valve mechanisms 28 and 30 when the clutch pedal 128 is released and the gear shift lever 132 is in a drive position. Thus, the fuel cut-off apparatus can operate only under decelerating conditions of the system as distinguished from an idling condition. Furthermore, the fuel cut-off apparatus is also provided with a disabling switch device 34' controlled bythe accelerator pedal 24' and functioning in a manner similar to the disabling switch device 34 hereinbefore described in connection with FIG- URES 1 and 2. The fuel cut-off system depicted in FIG- URE 8 may also include a switch 134 associated with the ignition switch assembly 136 of the automotive vehicle and connected in series with the switch devices 126, 34' and 124 to the parallel connected, solenoid operated valve mechanisms 28 and 30. Thus, closing of the ignition switch is required before the fuel cut-off system is operative in a manner similar to that hereinbefore described in connection with FIGURES 1 and 2 except for the manner in which the torque transmitting condition of the transmission is sensed.

What is claimed as new is as follows:

1. In a vehicle propulsion system having an internal combustion engine, a transmission having power coupling means connected to the engine, fuel supply means connected to the engine and fuel demand control means for regulating flow of fuel to the engine from the fuel supply means, means for minimizing passage of unburned fuel through the engine under a low fuel demand condition while the engine is decelerating comprising power operated valve means operatively connected to the fuel supply means and rendered operative to block flow of fuel to the engine, said fuel supply means including a fuel mixture passage portion conducting said flow of fuel and a combustion supporting fluid to the engine under control of the fuel demand control means and the power operated valve means, an intake cleaner means connected to the passage portion for supply of said combustion supporting fluid thereto, fuel diluting means interconnected between the intake means and the engine in by-pass relation to the fuel mixture passage portion for supplying the combustion supporting fluid to the engine simultaneously with said blockage of fuel flow by the power operated valve means, fluid pressure sensing means connected to the transmission for rendering the power operated valve means operative in response to development of a fluid pressure signal upon transmission of torque through the power coupling means and disabling means connected to the fuel demand control means for preventing operation of the power operated valve means except under said low fuel demand condition causing deceleration of the vehicle propulsion system.

2. In a vehicle propulsion system having an internal combustion engine, a transmission, power coupling means between the engine and the transmission, fuel supply means connected to the engine and fuel demand control means for regulating flow of fuel to the engine from the fuel supply means, means for minimizing passage of unburned fuel through the engine under a low fuel demand condition while the engine is decelerating comprising power operated valve means operatively connected to the fuel supply means and rendered operative to block flow of fuel to the engine, said fuel supply means including a fuel mixture passage portion conducting said flow of fuel and a combustion supporting fluid to the engine under control of the fuel demand control means and the power operated valve means, an intake cleaner means connected to the passage portion for supply of said combustion supporting fluid thereto, fuel diluting means interconnected between the intake means and the engine in by-pass relation to the fuel mixture passage portion for supplying the combustion supporting fluid to the engine simultaneously with said blockage of fuel flow by the power operated valve means, conditioning means connected to the power coupling means for rendering the power operated valve means operative in response to transfer of torque to the transmission through the power coupling means and disabling means connected to the fuel demand control means for preventing operation of the power operated valve means except under said low fuel demand condition causing deceleration of the vehicle propulsion system, said conditioning means comprising a fluid pressure responsive switch device connected in series with the disabling means, said power coupling means including a fluid transmitter having, an internal fluid pressure sensed by the fluid pressure responsive switch device.

3. The combination of claim 2 wherein said fuel diluting means comprises a solenoid operated valve device, a by-pass conduit interconnecting the intake means and the engine, said valve device being normally closed to prevent supply of the combustion supporting fluid through the by-pass conduit to the engine.

4. The combination of claim 3 wherein said disabling means comprises a normally closed switch connected in series with said solenoid operated valve devices to the source of electrical energy and means connecting the normally closed switch to the fuel demand control means for' ppening the switch in response to fuel demand accelerating the engine.

5.:- In a vehicle propulsion system having an internal combustion engine, a transmission, a fluid transmitter between the engine and the transmission, fuel supply means connected to the engine and fuel demand control means for regulating flow of fuel to the engine from the fuel supply means, means for minimizing passage of unburned fuel through the engine under a low fuel demand condition while the engine is decelerating com-' prising power operated valve means operatively connected to the fuel supply means and rendered operative to block flow of fuel to the engine, conditioning means for rendering the power operated valve means operative in response to transfer of torque to the transmission through the fluid transmitter and disabling means connected to the fuel demand control means for preventing operation of the power operated valve means except under said low fuel demand condition causing deceleration of the vehicle propulsion system, said conditioning means comprising a switch device responsive to internal fluid pressure in the fluid transmitter and connected in series with the disabling means for preventing operation of the power operated valve means.

6. The combination of claim 5 including fuel diluting means connected to the engine in by-pass relation to the fuel supply means for supplying combustion supporting fluid thereto simultaneously with said blockage of the flow of fuel to the engine.

References Cited 7 UNITED STATES PATENTS BENJAMIN W. WYCHE III, Primary Examiner US. Cl. X.R. 

